Like Jerry I have been shopping in the same place.
Thanks to someone showing an unusual marked wardens helmet with stars, this one was linked to a website.
Most un-official, as diamonds then stripes were used as rank, so following that line two stars should be for district warden, although the helmet should have been painted white.
Shell BMB 1939, liner is an J.C.S&W Ltd but can't see date, probably 1939. The cross bands are made of red/brown, while the rest of the liner is the normal black vulcanised fibre.